Strainer for the suction lines of pumps



Sept. 14, 1965 1-. P. HAWLEY STRAINER FOR THE SUCTION LINES OF PUMPS Filed Dec. 29. 1961 T.-T o. oY; o O 61 00o00000100000 oooof 000 000000 INVENTOR.

THOMAS P. HAWLEY ORNEYS.

.hose to lose suction sometimes 5" depths.

United States Patent M 3,206,036 STRAINER FOR THE SUCTION LINES OF PUMPS Thomas P. Hawley, 92 Joyce Road, Tenafly, NJ. Filed Dec. 29, 1961, Ser. No. 163,302 1 Claim. (Cl. 210-460) The invention relates to strainers, or water-sludge pickup baskets, for the intakes of pump suction lines.

In pumping out water and sluge from excavations, removing water and sand from flooded cellars, etc., it is exceedingly difficult to get out the last few inches of water and sand or sludge from the bottom of the area that is to be cleaned and made as dry as possible. Conventional strainers have projecting feet which, if resting on a hard surface bottom, hold the strainer in an elevated position which prevents removal of all the water. What happens is that suction cannot be maintained when the liquid level gets down to about 1 /2 or above sub-base level. In the case of round wire-baskets there is a strong tendency to develop a whirl-pool over thebasket so that air coming down the vortex will cause the pick-up These problems are made worse when the suction hoses are led off to one side of strainer so that the weight of the hose can tilt the strainer upwardly at its forward end with further loss of suction. If the strainer is resting on soft silt or on a sandy or muddy bottom, its projecting feet will be incapable of supporting it above the bottom. Under these conditions a heavy strainer of usual construction will often sink into the slit or mud and bacome quite useless. It has been an object of my invention to overcome these several problems.

According to my invention, the intake box of the strainer has its bottom opening covered by a strainer element presenting a substantially flat perforate surface at the lowermost part of the box. This means that there will be no supporting feet extending below the flat perforate surface, the intake box being free from any associated supporting structure extending below such surface. I have discovered that a strainer so constructed will literally float on a soft bottom and will pump liquid and sludge until the liquid level is much closer to the bottom than is possible with strainers heretofore available.

According to another feature of my invention, the top opening in the strainer box is located forwardly of the center of the box with the result that the tendency of the rear of the box to tip downwardly (or the front to tip upwardly) under the weight of the suction line is resisted by the increased bottom bearing area lying rearwardly of the top opening.

These and other features and advantages will be understood more fully from the following description of the best mode known to me for carrying out my invention.

In the drawings:

FIG. 1 is a top view of my improved strainer, one corner broken away in horizontal section.

FIG. 2 is a side elevational view of the same, partly broken away in central vertical cross section.

My strainer comprises an intake box 3 which in the preferred construction comprises a rectangular top 4 having downwardly extending flanges around the margins thereof forming the side walls 5 of the box and defining a bottom opening of comparatively greater area then the suction line 6 to which the strainer is connected. A strainer element 7 presents a substantially flat perforate surface 8 extending across the bottom opening defined by the aforesaid side walls 5 and upwardly extending perforate flanges 9 meeting and overlying such side walls.

The side walls of the box have opening or recesses 10 around the lower margins of the box. In my preferred construction these lateral openings are formed by 3,206,035 Patented Sept. 14, 1965 the lower edges of the side walls 5 in conjunction with projecting feet 11 at the corners of the box, and the upwardly extending perforate flanges 9 of the strainer element enclose the projecting feet 11.

The top 4 of the box has an opening 12 communicating with an L 13 for connection to the intake box. A suitable pipe flange 14 is secured in appropriate manner to the top of the box to provide a threaded connection to the L 13, and a coupling 15 provides means for quick and easy connection of the suction line 6 to a nipple 16 screwed into the other end of the L.

Intake box 3 may conveniently be made of 41" steel sheet flanged and welded at the corners. However, if desired, it may be formed as a casting. The strainer element may be formed of 20 gauge steel with 4" holes spaced on 71 centers. The pipe flange and L may be formed of malleable iron, and the hose coupling of brass. However, it will be understood that the materials used and the particular method of construction may be changed and modified as desired. In my embodiment as shown, the strainer element 7 is welded to the side walls 5 of the intake box.

According to my invention the substantially flat perforate surface 8 of the strainer element extends across the bottom opening of the intake box 3, the box being free from any associated supporting structure extending below such flat perforate surface. This feature is revealed clearly in FIG. 2 in which it will be seen that the flat perforate surface 8 is arranged at the lowermost part of the box. Thus the supporting feet 11 do not extend below this flat perforate surface. This helps to keep the strainer from sinking into a soft bottom and is also of great practical value from the standpoint of permitting liquid and sludge to bepurnped until the liquid level is much closer to the bottom than is possible with strainers heretofore available.

Also, according to my invention, the top opening 12 of the intake box is located forwardly of the center of the box so that the tendency of the rear of the box to tip downwardly under the weight of the horizontally extending suction line 6 is resisted by the increased bottom bearing area lying rearwardly of the top opening. This may be explained further with reference to the use of the strainer in pumping out basements where the intake box may be resting upon the hard concrete floor of the area being pumped. In this case the locating of the top opening 12 forwardly of the center of the box is helpful in resisting the tendency of the front of the box to tip upwardly. This is true because the principal weight of the hose coupling and adjacent section of the hose lies forwardly of the extending rear portion of the box, and therefore forwardly of the point about which the box would have to fulcrum in order to be tipped under the loading imposed by such weight. This feature in combination with the feature of enclosing the supporting structure for the box entirely within the strainer element is also of particular advantage in preventing the strainer from settling below the surface of a soft bottom. If desired, the feet 11 could be eliminated by welding the perforated sides 9 of the strainer element to the side walls 5 of the intake box. In this case the sides of the strainer element will constitute the entire supporting structure, and the lateral openings 10 in effect will extend entirely around the lower margin of the strainer.

Thus I have provided a strainer for pump suction lines comprising intake box 3 having a bottom opening of comparatively greater area than the suction line to which it is connected, and a top opening 12 provided with coupling means 13, 15 for connecting the strainer to a suction line 6, the intake box having lateral openings 10 around its lower margins, and a strainer element 7 presenting a substantially flat perforate surface extending across the bottom opening at the lowermost part of the intake box, the box being free from any associated supporting structure extending below such flat perforate surface.

The terms and expressions which I have employed are used in a descriptive and not a limiting sense, and I have no intention of excluding equivalents of the invention described and claimed.

I claim: A strainer for pump suction lines comprising an imperforate intake box having a bottom opening of comparatively greater area than the suction line to which it is strainer from below, the intake box being free from any associated supporting structure extending below said flat perforate surface, said lateral openings around the lower margins of the intake box being formed by the lower edges of the side walls of the box in conjunction with downwardly projecting feet, and said strainer element having upwardly extending, perforate flanges meeting the side walls of the box and enclosing said downwardly projecting feet, said top opening being connected to an L providing for connection to a suction line extending horizontally beyond the read of the suction box, and said top opening being located forwardly of the center of the box whereby tendency of the rear of the box to tip downwardly under the weight of the horizontally extending suction line is resisted by the increased bottom bearing area lying rearwardly of the top opening, and the intake box having a generally rectangular configuration at the rear end thereof forming a stable support against suchdovvnward tipping of the rear of the box.

References Cited by the Examiner UNITED STATES PATENTS 1,865,209 6/32 Pretsch 210-461 1,945,824 2/34 Saxe 210 460 2,285,997 6/42 Mino 210461X FOREIGN PATENTS 1,818 11/86 Great Britain. 502,765 3/39 Great Britain.

REUBEN FRIEDMAN, Primary Examiner.

HERBERT L. MARTIN, Examiner. 

